# Paul Davies enumerates all possible explanations of the fine tuning debate (Anthropic Principle) **URL:** \ **Category:** Great Debates\ **Created:** [November 20, 2010, 10:25pm UTC](https://boards.straightdope.com/t/paul-davies-enumerates-all-possible-explanations-of-the-fine-tuning-debate-anthropic-principle/561373 "2010-11-20T22:25:07Z")\ **Posts on this page:** 6\ **Page:** 3
**Author:** ![iamnotbatman](https://avatars.discourse-cdn.com/v4/letter/i/858c86/32.png) [@iamnotbatman](https://boards.straightdope.com/u/iamnotbatman)\ **Post date:** [November 27, 2010, 6:28am UTC](https://boards.straightdope.com/t/paul-davies-enumerates-all-possible-explanations-of-the-fine-tuning-debate-anthropic-principle/561373/41 "2010-11-27T06:28:20Z")
For what it’s worth (taking my physics hat off, putting on philosophy/logician hat) here are my comments on the list from your OP: > [@](#): > > 1. The absurd universe > > Our universe just happens to be the way it is. Exact same as #2. Absurd =\> unique. There must be a _reason_ for the universe being ‘absurd’, even if that reason appears absurd. > [@](#): > > 1. The unique universe > > There is a deep underlying unity in physics which necessitates the universe being the way it is. Some Theory of Everything will explain why the various features of the Universe must have exactly the values that we see. Definitely possible, and it also can subsumes #3, since the ‘deep underlying unity’ may necessitate a multiverse. > [@](#): > > 1. The multiverse > > Multiple Universes exist, having all possible combinations of characteristics, and we inevitably find ourselves within a Universe that allows us to exist. Definitely possible. Seems the least arbitrary motivating principle to me, and one that transcends man’s biased and parochial instinct about which universes are somehow more “correct” than others. Complete ‘symmetry’ in the sense that no one universe is arbitrarily/magically extant at the expense of others. > [@](#): > > 1. Creationism > > A creator designed the Universe with the purpose of supporting complexity and the emergence of Intelligence. Exact same as #7. > [@](#): > > 1. The life principle > > There is an underlying principle that constrains the universe to evolve towards life and mind. Nonsense. In any case superfluous (subsumed by #2). > [@](#): > > 1. The self-explaining universe > > A closed explanatory or causal loop: “perhaps only universes with a capacity for consciousness can exist.” This is Wheeler’s Participatory Anthropic Principle (PAP). Possible, and has a certain cuteness/tidiness about it. As a general rule: don’t underestimate Wheeler. He was no crackpot. Unfortunately this gets into another can of worms: the measurement problem in QM, which is in itself a contentious subject, and probably not worth getting into here. > [@](#): > > 1. The fake universe > > We live inside a virtual reality simulation. Exact same as #4. Of course, this doesn’t solve the fine-tuning problem in the simulator’s universe. ---
**Author:** ![Novelty\_Bobble](https://avatars.discourse-cdn.com/v4/letter/n/a3d4f5/32.png) [@Novelty\_Bobble](https://boards.straightdope.com/u/Novelty_Bobble)\ **Post date:** [November 27, 2010, 9:30am UTC](https://boards.straightdope.com/t/paul-davies-enumerates-all-possible-explanations-of-the-fine-tuning-debate-anthropic-principle/561373/42 "2010-11-27T09:30:00Z")
> [@Measure\_for\_Measure](#): > > This might falsify my hypothesis: we could have a chain of sequential universes as opposed to a number of universes running in parallel. Then again time is an aspect of our universe so, no, I have no idea what I’m talking about. […] Is this a variant of #3, the multiverse after all? > > Incidentally, our friend wikipedia maintains that a big crunch is possible, though not observationally supported at present. [Big Crunch - Wikipedia](http://en.wikipedia.org/wiki/Big_Crunch) I think it’d be a hybrid of 2 & 3 but hey! what the heck do I know? It’s a bit like that cat in the box, all possibilities are explored until such time as we are around to observe it. Then it doesn’t actually matter whether they are sequential or concurrent as we only ever find ourselves in one of them and the others are invisible to us either temporally or dimensionally. ---
**Author:** ![Measure\_for\_Measure](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/measure_for_measure/32/557_2.png) [@Measure\_for\_Measure](https://boards.straightdope.com/u/Measure_for_Measure)\ **Post date:** [November 29, 2010, 2:55am UTC](https://boards.straightdope.com/t/paul-davies-enumerates-all-possible-explanations-of-the-fine-tuning-debate-anthropic-principle/561373/43 "2010-11-29T02:55:46Z")
> [@Measure\_for\_Measure](#): > > Let me be succinct: **we live in a multiverse**. I can no longer support that contention: we may live in a monoverse. The multiverse necessity hypothesis gives short shrift to the compelling “Something we haven’t thought of” explanation of the fine tuning puzzle. The Participatory Anthropic Principle (PAP) supports fine tuning in a plausible monoverse: multiverses are no longer necessary within that framework. Furthermore PAP bears a family resemblance to other interpretations of quantum mechanics: the latter have the virtue of having some empirical support. So while the multiverse hypothesis is consistent with much of Davies’ taxonomy, it does not cover all of it. I’ll note that both both the PAP explanation and the set involving parallel universes are …odd. Life and physics are like that sometimes. ---
**Author:** ![jackdavinci](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jackdavinci/32/3259_2.png) [@jackdavinci](https://boards.straightdope.com/u/jackdavinci)\ **Post date:** [April 30, 2012, 4:26pm UTC](https://boards.straightdope.com/t/paul-davies-enumerates-all-possible-explanations-of-the-fine-tuning-debate-anthropic-principle/561373/44 "2012-04-30T16:26:34Z")
This is a dense thread so I’m going to try and give a more thought out answer later but I wanted to bring up something I didn’t see mentioned. Although I think the fine tuning issue does present some evidence for the multiverse (my conception of which is similar to Septimus’ and the strange loops mentioned, with a dash of quantum suicide), there are plenty of other arguments for it, and in fact the fine tuning issue might not be as much an issue as it’s usually made out to be. I read a paper (I’ll try to find a link later) that basically said, sure, if you modify one of the constants out of a narrow range, that seems to screw up everything. But! If you modify more than one at the same time, they balance out and you get other interesting life and chemistry friendly scenarios. And they gave some examples. ---
**Author:** ![Thudlow\_Boink](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/thudlow_boink/32/320_2.png) [@Thudlow\_Boink](https://boards.straightdope.com/u/Thudlow_Boink)\ **Post date:** [April 30, 2012, 10:17pm UTC](https://boards.straightdope.com/t/paul-davies-enumerates-all-possible-explanations-of-the-fine-tuning-debate-anthropic-principle/561373/45 "2012-04-30T22:17:26Z")
[In _this_ universe, the many-worlds interpretation of quantum mechanics is false.](http://abstrusegoose.com/457) ---
**Author:** ![erislover](https://avatars.discourse-cdn.com/v4/letter/e/71e660/32.png) [@erislover](https://boards.straightdope.com/u/erislover)\ **Post date:** [May 1, 2012, 3:22am UTC](https://boards.straightdope.com/t/paul-davies-enumerates-all-possible-explanations-of-the-fine-tuning-debate-anthropic-principle/561373/46 "2012-05-01T03:22:28Z")
[A complete theory of everything (will be subjective)](http://arxiv.org/abs/0912.5434) I can’t say whether it is particularly good, I just found it interesting. There’s a funny bit in justifying Ockham’s razor about the shortest program consistent with our observations. Unfortunately it’s a [well-known result](http://math.ucr.edu/home/baez/surprises.html) that beyond certain (unbelievably low) limits this property cannot be formally proven. It’s a bit curious to try to justify Ockham’s razor this way, as it’s not at all clear what one has actually shown. It’s using a metric in one sense that is provably unusable in another not totally unrelated sense, a bit like throwing a dart and saying you most likely hit a single score, not a double triple or bullseye, but never being able to actually look at the board ever… even in the first place to know where the bullseye and triples are. I’m not saying the demonstration is wrong, I can’t really speak to it, but it feels a little weird to me. [Previous page](https://boards.straightdope.com/t/paul-davies-enumerates-all-possible-explanations-of-the-fine-tuning-debate-anthropic-principle/561373.md?page=2)